Recent content by John Mulcahy

RTA window

You could play pink periodic noise and use the RTA, suitable RTA settings are included in the linked help.

Builds updated today (beta 133) with these changes: Added: AirDSP by Acoustas equaliser entries Changed: siggen.properties has an entry for the signal generator frequency tooltip Fixed: dBFS data of minimum phase response could be 3 dB lower than the source

No, the electrical impedance model has a dR component to allow for measurement errors and the effects of coil temperature. If there isn't sufficient low frequency data to estimate that it will be forced to zero (since V5.40 beta 130).

Sweep measurements are designed to reject uncorrelated noise. Use the RTA with a tone.

Yes, that's a reasonable approach, and it's why the EQ window has tools to find resonances, show live updates of the predicted waterfall as filters are adjusted and show pole-zero plots for the response and the filters. However, the few studies that have been done on the audibility of low...

I have fixed that for the next build, in the meantime you can scale the IR data on the Impulse graph by 3.01 dB before export.

RMS averaging or moving mic method probably best for that.

Use cross correlation alignment and vector averaging if you need to with with an impulse response, for EQ RMS or dB averages are often more suitable. Aligning SPL is important if the measurements are from significantly different distances from the mic. Cross correlation alignment is unlikely to...

The alignment tool impulse alignment mode uses zero phase 1/3 octave filters. The Filtered IR graph is primarily aimed at examination of individual bands of RT60 analysis, it has options for 1 octave or 1/3 octave and forward, zero phase or time reversed filtering.

That's because the imported impulse responses only have that much data, typical of Audyssey imports. For longer responses measure with REW.

That's outside the scope of REW. Low level access to interfaces is handled by code the Java runtime loads, it is possible to substitute that as @phofman did for WASAPI Exclusive and Linux ALSA PCM using his csjsound-provider project, something similar would be needed to improve the macOS...

I don't know what Q configuration Trinnov uses, you can find out by measuring the filter shapes it produces with different settings on a line output and seeing what configurable equaliser setting produces the same shapes. You might find answers to the other questions on threads about the Ci...

Estimate IR delay uses cross-correlation with a minimum phase version of the response, it isn't suitable for alignment though. For that you should measure with a timing reference (as you appear to have done) and use the Alignment tool on the All SPL graph.